Boundary-value problems for differential equations not solved with respect to the derivative, in the space of bounded number sequences. Neliniini Kolyvannya, [S. l.], v. 10, n. 3, p. 391–415, 2007. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/447. Acesso em: 21 jan. 2026.